Aminoglycosides

Hello, we, byeolnim lee and Haeon lee, re-write about Aminoglycosides. And, we have a question. In the textbook, Gentamicin sulfate is effective against MRSA. But you stated,"One point to clarify is that aminoglycosides are not effective in treating MRSA." I wonder what is the correct information. 

Origin

• Streptomycin sulfate from the bacterium streptomyces griseus in 1944.

Actions

• Inhibition of bacterial protein synthesis; bactericidal effect

General Information

§  Serious infections, since good activity against multidrug-resistant Gram-negative pathogens, such as pseudomonas aeruginosa.

§  Active against both Gram-negative and gram-positive infections.

§  Not effective in MRSA.

§  Clinical application: bacteremia, endocarditis, nosocomial pneumonias, intra-abdominal infections.

Indication

• Respiratory tract
•  Bone and joint
• Skin, and soft-tissue infections
•  Pelvic inflammatory disease
•  Hepatic coma
• Decreases bacteria in the bowel
• Tuberculosis

Route & Dosage

·         Amikacin sulfate (Amikin)

—         A/: IM/IV: 10 to 15 mg/kg/d q8 to 12h; max: 15 mg/kg/d

—         C: IM/IV: 7.5 to 22.5mg/kg/d in divided doses; max:15 mg/kg/d

—         TDM: peak: 25 to 35 mcg/mL; trough: < 5 mg/ml

·         Gentamicin sulfate (Ganamycin)

—         A: IM/IV: 3 to 6 mg/kg/d in 2 to 3 in divided doses

—         C: IM/IV: 2 to 2.5mg/kg q8h

—         TDM: peak: 5 to 8 mcg/mL; trough: 0.5 to 2 mcg/mL

·         Kanamycin sulfate (Kantrex):

—         A/C: IM/IV: 10 to 15mg/kg/d in divided doses

·         Neomycin sulfate Myciguent (Neo-Fradin)

—         Bowel prep: A: PO: 1 g q1h for 4 doses; then 1 g q4h for 5 doses

—         Hepatic coma: A: PO: 1 to 3 g q6h for 5 to 6 d; max: 12 g/d

·         Streptomycin sulfate (Streptomycin)

—         A: IM: 1 to 2 g/d

—         C: IM: 20 to 40 mg/kg/d

—         TDM: peak: 20 to 35 mcg/mL; trough: <10 mcg/mL

·         Tobramycin sulfate (Nebcin):

—         A: IM/IV: 3 to 5 mg/kg/d in divided doses

—         C: IM/IV: 2.5mg/kg/d in divided doses

—         TDM: peak: 4 to 8 mcg/mL; trough: 0.5 to 2 mcg/mL

Interactions

§  With penicillins, efficacy ↓

§  With aminoglycosides, oral anticoagulants ↑

§  With ethacrynic acid, ototoxicity ↑

§  With beta lactams, efficacy ↑

§  With gentamicin, streptomycin, penicillin G and ampicillin, efficacy ↑  

Side  Effects

• Nephrotoxicity
• Ototoxicity                                        
• Photosensitivity             
• Nausea, Vomiting, tremors, tinnitus, pruitus, and muscle cramps           

Contraindications

• Hypersensitivity
• Severe renal disease
• Pregnancy, and breastfeeding

Nursing Intervention

• Record vital signs
•  Monitor intake/output.

• Check lab results (renal, liver function)

• Medical history related to renal or hearing disorders.
• Send sample from infected area.

• Check for hearing loss to observe ototoxicity.

Patient Teaching

• Unless fluids are restricted, encourage client to increase fluid intake.
• Instruct client never to take leftover antibiotics.
• Observe side effect.
• Concern about sun exposure.

Interesting Information

According to Pagkalis, Mantadakis, Mavros, Ammari andFalagas (2011),
1. The once-daily dosing schedule provide a longer time of administration until the threshold for nephrotoxicity is met.
2. Regarding ototoxicity, no dosing regimen appears to be less ototoxic than another.
3. Close monitoring need to minimize the toxicities and the clinical failures.

References

Kee, J., Hayes, E., & McCuistion, L. (2012). Pharmacology; a nursing process approach (7th ed.). St. Louis, MO: Elsevier.

Pagkalis, S., Mantadakis, E., Mavros, M.N., Ammari, C., & Falagas, M. E. (2011). Pharmacological consideration for the proper clinical use of aminoglycosides. Drugs, 71(17), 2277-2294. doi:10.2165/11597020-000000000-00000

Radigan, E. A., Gilchrist, N. A., & Miller, M. A. (2010). Management of Aminoglycosides in the Intensive Care unit. Journal Of Intensive Care Medicine (Sage Publications Inc.), 25(6), 327-342. doi:10.1177/0885066610377968